A common type of fluid pressure energy translating device comprises a housing which contains a rotating group of the axial piston type such as shown in U.S. Pat. Nos. 2,776,628, 3,457,873 and 3,481,277.
In devices of this type, a rotating group is mounted in a cavity of a housing and comprises a rotary cylinder barrel in the cavity which is driven or drives a shaft and has a plurality of axial cylinders in which pistons are positioned. The ends of the pistons are connected to shoes which engage an inclined surface and the cylinders communicate through openings with an inlet or outlet in a valve plate positioned adjacent and engaging the cylinder barrel. As the barrel rotates, the fluid is either pumped into or out of the cylinders depending upon whether the device is being used as a pump or motor.
In the maintenance of such a device, it is necessary to take the device apart and replace the various components such as the cylinder barrel, pistons, shoes and associated seals. Handling of the separate parts is costly and time consuming.
Among the objectives of the present invention are to provide a fluid pressure energy translating device which will permit rapid field replacement of the rotating components and seals; which utilizes a cartridge containing the rotating parts and seals which may be readily removed and replaced by a new cartridge; which cartridge can readily be engaged with a drive shaft rotatably mounted in a housing and located within the cavity of the housing.
In accordance with the invention, the fluid pressure energy translating device comprises a housing defining a cavity, a drive shaft having a portion thereof rotatably mounted in the housing and extending into the cavity. The cavity has an open end remote from said drive shaft. A valve block closes the open end of said housing. A rotating group cartridge is positioned in the cavity between the valve block and is drivingly engaged with the shaft. The cartridge comprises a valve plate engaging the valve block and an angle block. A rotatable cylinder barrel is interposed between the valve plate and angle block in abutment with the valve plate and in driving relation with the drive shaft. The cylinder barrel has a plurality of piston cylinders, each of which has a port for communicating the cylinders with a face of the valve plate, a piston in each said cylinder, shoes connected to the pistons and engaging an inclined surface on the angle block and means interconnecting the valve plate and angle block to form a removable cartridge.